Answer:
Ask your parents when they are in a good mood.
Ask to have the sleepover at a convenient time.
Be polite instead of demanding.
Keep the first sleepover simple.
Offer to do something kind in exchange.
Show them that it will be a good opportunity for you to socialize
In what way ? And what king ?
Sponsorship is basically when you receive financial support from someone.
It's largely done for companies.
Sorry if this doesn't really help you. =(
